README: document the new sway_setup prompt-based flow

README.md

@@ -89,24 +89,32 @@ If you skip this step, the omp config files will still land (they're not encrypt
 
 ## Sway / Wayland desktop stack
 
-Sway + wofi + foot + waybar + swaybg/lock/idle + grim/slurp + wl-clipboard is opt-in per host. Pis don't get it (headless); x86_64 desktops do automatically.
+Sway + wofi + foot + waybar + swaybg/lock/idle + grim/slurp + wl-clipboard is opt-in at bootstrap time. The user decides per-box.
 
-**Default behavior** (set in `.chezmoi.yaml.tmpl`):
+**Bootstrap prompt:** when you run `chezmoi init` for the first time on a new box, you'll be asked:
-- `data.sway: true` on hostnames matching `miche`, `byte`, `kaiser` (and any suffix like `byte-arch`)
-- `data.sway: false` on every other host
 
-**Manual override** (per box, takes precedence over hostname rule):
+```
+sway_setup (default false)? [y/N]
+```
+
+Answer `y` to install the packages + write the configs. Answer `N` (or just press enter) to skip. The answer is captured in `data.sway_setup` in the rendered `~/.config/chezmoi/chezmoi.yaml` and never re-asked.
+
+**Subsequent flips** (per box, takes precedence over the bootstrap answer):
 ```bash
-# Force ON (e.g. you set up a new Pi with a screen):
+# Enable sway after the fact:
 touch ~/.config/chezmoi/features/sway
 chezmoi apply
 
-# Force OFF (e.g. running a desktop headless as a server):
+# Disable sway (e.g. running a desktop headless as a server):
 touch ~/.config/chezmoi/features/no-sway
 rm -f ~/.config/chezmoi/features/sway
 chezmoi apply
 ```
 
+**Migration from hostname-allowlist:** the previous design auto-enabled sway on hostnames matching `miche`/`byte`/`kaiser`. That was removed. Existing desktops that already had sway installed kept the `~/.config/chezmoi/features/sway` marker, which now serves as the override-on signal — so they still have `sway_setup: true` without re-prompting.
+
+**Migration of `chezmoi.yaml`:** if you ran the new template via SSH (no TTY), the prompt fails with "could not open a new TTY". Run it interactively (`chezmoi init`) from a real terminal, OR pass `--promptBool sway_setup=true|false` to set the value without prompting.
+
 The `run_once_40-install-sway.sh` script:
 - exits 0 with no side effects on non-sway boxes
 - installs `sway wofi foot swaybg swaylock swayidle grim slurp waybar wl-clipboard` via `pacman` (arch) or `apt` (debian)
@@ -115,6 +123,8 @@ The `run_once_40-install-sway.sh` script:
 
 The configs in `dot_config/{sway,foot,wofi,waybar,mako}/` are placed unconditionally — they're harmless on Pis (no tools to read them).
 
+Sway is NOT auto-launched. It's installed as a tool you run manually from a TTY (`sway` from TTY1) for light desktops. The install and configs sit ready; launching is your call.
+
 ## Editing dotfiles
 
 ```bash